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Ralph Walter Graystone Wyckoff
Ralph Walter Graystone Wyckoff
Born	August 9, 1897; Geneva, New York
Died	November 3, 1994 (aged 97); Tucson, Arizona
Nationality	American
Alma mater	Hobart College; Cornell University
Known for	X-ray crystallography; Wyckoff positions
	Scientific career
Institutions	Carnegie Institution for Science; Rockefeller University; National Institutes of Health; University of Arizona
Doctoral advisor	Louis Munroe Dennis
Other academic advisors	Shoji Nishikawa

Ralph Walter Graystone Wyckoff, Sr. (August 9, 1897 – November 3, 1994), or simply Ralph Wyckoff, was an American chemist and pioneer of X-ray crystallography. He also made contributions to vaccine developments against epidemic typhus and other viruses.^[1]^[2]

Biography

Wyckoff was the son of judge Abram Ralph Wyckoff and Ethel Agnes Catchpole. He studied at Hobart College, where he obtained a Bachelor of Science in 1916. He continued his studies at Cornell University, where he obtained his Ph.D. in 1919.^[3] In 1916, he published his first scientific paper (of more than 400) at the age of nineteen in the Journal of the American Chemical Society. Under Shoji Nishikawa, he presented his thesis about the crystallographic resolution of the structures of NaNO₃ and CsICl₂ in 1919.

Wyckoff continued working in X-ray crystallography and wrote several books about the topic. Wyckoff's 1922 book, The Analytical Expression of the Results of the Theory of Space Groups, contained tables with the positional coordinates, both general and special, permitted by the symmetry elements. This book was the forerunner of International Tables for X-ray Crystallography, which first appeared in 1935. Both general and special positions are also called Wyckoff positions in his honor.

In 1927, Wyckoff moved to the Rockefeller University (then called The Rockefeller Institute for Medical Research) to take up studies of bacteria and, especially, viruses. While there, he photographed the growth of living cells using ultraviolet light^[4] and determined the structure of urea.^[5] He left Rockefeller in 1937. After leaving there, he worked in private industry on the Western equine encephalitis virus. This work resulted to the creation of a vaccine against it. During World War II, he developed a vaccine against epidemic typhus.^[5] In 1943, he moved to Michigan where he worked for the University of Michigan and the Michigan State Department of Health. In Ann Arbor, he invented a technique to take three-dimensional electron microscope images of bacteria using a "metal shadowing" technique.^[6] Robley C. Williams worked with him to develop the technique. From 1946 to 1952, he researched macromolecules and viruses at the National Institutes of Health in Bethesda, Maryland. In 1948, he helped found the International Union of Crystallography and served as vice-president and president from 1951 to 1957.^[5] In 1959, appalled by growing bureaucracy at the NIH, he took the job of professor of microbiology and physics at the University of Arizona in Tucson, where he was forced to retire at the age of 80.